New Delhi -LRB- CNN -RRB- -- Flooding in southern India in the wake of a tropical cyclone has killed 25 people in the past few days and driven tens of thousands of others from their homes , authorities said Tuesday .

The severe weather has caused flooding affecting 5,250 square kilometers -LRB- 2,000 square miles -RRB- of agricultural land in the state of Andhra Pradesh , according to Vinod Kumar , an official at the state 's disaster management department .

Cyclone Nilam roared into India 's southeastern coast last week , killing at least 15 people in the state of Tamil Nadu and running a large oil tanker aground on the shore near Chennai .

The storm had already been drenching coastal areas with rain as it loitered over the sea north of Sri Lanka before it made landfall . It brought more than a month 's rainfall in just a few of days , according to CNN meteorologist Ivan Cabrera .

The `` high impact , long duration '' nature of the downpours `` overwhelmed the rivers and streams '' and led to the disastrous flooding , Cabrera said .

About 70,000 people in Andhra Pradesh , which is north of Tamil Nadu , have been relocated to temporary shelters , Kumar said Tuesday . The flooding has killed 25 people in the state , he said .

The full extent of the damage to crops wo n't be known until after the flood waters recede , according to authorities .

Tropical cyclones tend to occur in the Bay of Bengal and the Arabian Sea during the April-to-June and September-to-November periods .

A violent tropical storm killed at least 23 people in southeastern Bangladesh last month . And a powerful cyclone that hit India and Bangladesh in May 2009 killed at least 180 people .

CNN 's Jethro Mullen in Hong Kong contributed to this report .

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About 70,000 people are in temporary shelters because of the floods

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Heavy rain from a tropical storm overwhelmed the water system

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The flooding has killed 25 people in the state of Andhra Pradesh

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It has also affected thousands of square kilometers of crops